Hornady's 7th ed. Reloading Handbook errata

[kg42]

In case you didn't get the card:
(or http://www.hornady.com/media/7th_errata2.pdf)

[versifier]

That is the perfect illustration of why any loader should have three or more sources of data. All the info is compiled and typeset by.... human beings. We all screw up once in a while. Sometimes we screw up big time. Even my ex admits to one or two mistakes in her life, though not to me.

Seriously though, if you have only two sources and there is a notable difference between what they tell you, how do you know which one is safe and which is a quick ticket to ground zero? Even the best of sources has an occasional error, and just because it's in print doesn't necessarily mean that it's correct. I am often asked why a loader can't get by with just one source, books are expensive, etc., etc. I respond by asking a few questions: What's your gun worth? What will it be worth in several dozen pieces, some of which my have to be removed from your skull or the bodies of bystanders? What's the deductible on your health insurance? How much does a trip to the emergency room cost? Reconstructive or cosmetic surgery? What does the average funeral cost? After that, the price of a couple more manuals doesn't seem so high anymore.

How many are on your shelf?

[bullshot]

I also cross reference loading manuals. I have bought all the popular brands for the last 40 or so years. Ever notice that the Lyman manuals are a lot less conservative than the other manuals. I always thought that it was because thy didn't market bullets or powder but thats just a guess. Anyway my total agreement in cross checking, mistakes are made.
Bob
Bullshot

[versifier]

Welcome to the forum, bullshot.
I have noticed that. I think a big part of it (My opinion, and I may be wrong) is that they don't update all their data for new editions. Plus, there have been not only changes in powders over the years, but serious changes in the way we measure pressure. A pizeoelectric transducer epoxied to the outside of the chamber is way way more accurate than the old copper crusher/pressure barrel method. (I would like to think they didn't do it by watching the primers. ) When modern testing was developed, may loads previously considered safe were found not so.

Most bullet makers often update their data because they have to constantly test new batches of bullets to make sure they're within spec and they generate the updated data as part of the process. I have found that data from the bullet makers is generally more uniform from manual to manual, and that they are less likely to have mistakes. But you can still find a few in even the best ones from time to time.